NEW YORK (Reuters Health) - Chronic infection with
hepatitis C virus (HCV) is associated with an increased rate of
hypothyroidism and thyroid autoimmunity, according to a report in the
July 1st issue of The American Journal of Medicine.

"The significant association of chronic hepatitis C with
hypothyroidism and thyroid autoimmune phenomena implies that these
patients should be screened for thyroid function on a periodic basis,"
lead author Dr. Alessandro Antonelli from the University of Pisa School
of Medicine, Italy, told Reuters Health. "A substantial proportion-13%
in our series-will have hypothyroidism, and thus might benefit from
treatment."

Thyroid involvement in HCV-infected patients has been reported
previously, the authors explain, but little is known about the
prevalence and nature of thyroid disorders in such patients.

Dr. Antonelli and colleagues investigated the prevalence and
features of thyroid disorders in 630 consecutive patients with chronic
hepatitis due to HCV infection.

Significantly more HCV-infected patients than controls had positive
anti-thyroid peroxidase or anti-thyroglobulin autoantibodies, the
results indicate, and hypothyroidism (TSH greater than 4 mIUnits/mL)
was significantly more common among HCV-infected patients (13%) than
among controls (3-5%).

Both markers of autoimmunity were more common in hypothyroid
HCV-infected patients than in euthyroid HCV-infected patients, the
researchers note.

"We are planning a population based epidemiological study to assess
the association between thyroid disorders and HCV infection," Dr.
Antonelli added. "The possible association of HCV infection with
thyroid differentiated cancer and diabetes mellitus is under
investigation not only in patients with HCV infection, but also in
patients with HCV associated mixed cryoglobulinemia."